3 files changed, 39 insertions, 7 deletions
diff --git a/include/llvm/Support/DebugLoc.h b/include/llvm/Support/DebugLoc.h
index 362390f628..6814f63d9e 100644
--- a/include/llvm/Support/DebugLoc.h
+++ b/include/llvm/Support/DebugLoc.h
@@ -66,7 +66,7 @@ namespace llvm {
   };
 
   // Specialize DenseMapInfo for DebugLocTuple.
-  template<>  struct DenseMapInfo<DebugLocTuple> {
+  template<> struct DenseMapInfo<DebugLocTuple> {
     static inline DebugLocTuple getEmptyKey() {
       return DebugLocTuple(0, 0, ~0U, ~0U);
     }
@@ -85,9 +85,9 @@ namespace llvm {
              LHS.Line         == RHS.Line &&
              LHS.Col          == RHS.Col;
     }
-
-    static bool isPod() { return true; }
   };
+  template <> struct isPodLike<DebugLocTuple> {static const bool value = true;};
+
 
   /// DebugLocTracker - This class tracks debug location information.
   ///
diff --git a/include/llvm/Support/ValueHandle.h b/include/llvm/Support/ValueHandle.h
index a9872a7be1..82c3caeb3a 100644
--- a/include/llvm/Support/ValueHandle.h
+++ b/include/llvm/Support/ValueHandle.h
@@ -254,15 +254,18 @@ struct DenseMapInfo<AssertingVH<T> > {
   static bool isEqual(const AssertingVH<T> &LHS, const AssertingVH<T> &RHS) {
     return LHS == RHS;
   }
-  static bool isPod() {
+};
+  
+template <typename T>
+struct isPodLike<AssertingVH<T> > {
 #ifdef NDEBUG
-    return true;
+  static const bool value = true;
 #else
-    return false;
+  static const bool value = false;
 #endif
-  }
 };
 
+
 /// TrackingVH - This is a value handle that tracks a Value (or Value subclass),
 /// even across RAUW operations.
 ///
diff --git a/include/llvm/Support/type_traits.h b/include/llvm/Support/type_traits.h
index ce916b5fcc..1f3f1e4f89 100644
--- a/include/llvm/Support/type_traits.h
+++ b/include/llvm/Support/type_traits.h
@@ -17,6 +17,8 @@
 #ifndef LLVM_SUPPORT_TYPE_TRAITS_H
 #define LLVM_SUPPORT_TYPE_TRAITS_H
 
+#include <utility>
+
 // This is actually the conforming implementation which works with abstract
 // classes.  However, enough compilers have trouble with it that most will use
 // the one in boost/type_traits/object_traits.hpp. This implementation actually
@@ -24,6 +26,33 @@
 
 namespace llvm {
 
+/// isPodLike - This is a type trait that is used to determine whether a given
+/// type can be copied around with memcpy instead of running ctors etc.
+template <typename T>
+struct isPodLike {
+  static const bool value = false;  
+};
+  
+// pointers are all pod-like.
+template <typename T>
+struct isPodLike<T*> { static const bool value = true; };
+
+// builtin types are pod-like as well.
+// There is probably a much better way to do this.
+template <> struct isPodLike<char> { static const bool value = true; };
+template <> struct isPodLike<unsigned> { static const bool value = true; };
+template <> struct isPodLike<unsigned long> { static const bool value = true; };
+template <> struct isPodLike<unsigned long long> {
+  static const bool value = true;
+};
+  
+  
+// pairs are pod-like if their elements are.
+template<typename T, typename U>
+struct isPodLike<std::pair<T, U> > {
+  static const bool value = isPodLike<T>::value & isPodLike<U>::value;
+};
+  
 namespace dont_use
 {
     // These two functions should never be used. They are helpers to